1. Field of the Invention
The present invention generally relates to the construction of trailers for towing behind motor vehicles and, more particularly, is concerned with an improved trailer frame incorporating stabilized caster swivel and bounce motion dampening assemblies.
2. Description of the Prior Art
One common practice for transporting many different loads is to tow a load-carrying trailer behind a motor vehicle. As well-known in the prior art, such trailer typically includes a longitudinal frame mounting a load-carrying bed, enclosure or container and a pair of laterally-spaced ground-engaging wheels rotatably mounted to opposite ends of a transverse axle being attached to an undercarriage suspension arrangement which supports the frame. Also, such trailers usually have an elongated tongue rigidly attached to the forward end of the mobile frame. The front end of the tongue typically is pivotally connected about a vertical axis by a ball and socket hitch to the rear end of the towing motor vehicle to permit ease in turning the vehicle and trailer.
The prior art trailers having the construction described above usually function satisfactorily under normal weather and road conditions. However, in adverse weather and road conditions, such as strong wind currents and rough and uneven roads, trailers of such general construction experience difficulties. Because of the pivotal connection about the vertical axis between the trailer and towing vehicle, the trailer can develop an unstable and dangerous side-to-side swaying which oftentimes results in overturning of the trailer and damage to the towing vehicle unless the speed of the towing vehicle and trailer is slowed to an unacceptably low rate for normal highway traffic flow.
Trailers pivotally hitched about a horizontal axis to the rear of the towing vehicle and supported by a caster wheel having a swivel-type connection to the trailer frame have been attempted in the prior art. However the well-known tendency of swivel-type caster wheels to develop an unstable shimmy or oscillation at normal highway traffic speeds and the failure of any operable system to date to prevent this tendency has made a caster wheel supported trailer frame an unacceptable alternative to the above-described prior art trailer frame construction in current widespread use.
Consequently, a need still exists for improvement in trailer construction so as to overcome the above-described problems without introducing a new set of problems in their place.